1. Field of the Invention
The invention relates to a fuel cell and, more particularly, to a housing case that forms an outside surface of a fuel cell.
2. Description of the Related Art
Research and development is now carried out on a vehicle equipped with a fuel cell electricity generating system capable of utilizing electricity generated during reaction between hydrogen and oxygen. Normally, fuel cells incorporated in a fuel cell electric power generating system are provided in the form of a fuel cell stack having many stacked unit cells. With regard to a fuel cell stack, a securing method has been proposed in which a fuel cell stack is secured by a pair of end plates that are disposed on both sides of the stack in the direction of stacking unit cells.
If a fuel cell having a fuel cell stack as mentioned above is installed in a vehicle, there arise dangers of positional deviation and deformation of stacked unit cells being caused by a torsional force applied to the fuel cell due to a torsion of a body of the vehicle or vibrations that occur in the vehicle. Such a slight deviation or deformation may cause leakage of a cooling gas, a fuel gas or the like. Furthermore, such a deviation or deformation will reduce the stability of the mounting fixture of the piping for supplying and discharging a fuel gas, an oxidative gas and a coolant, and the electric system wiring, etc. to the stack, and will reduce the mounting precision thereof. Considering stable installation of the fuel cell into a vehicle, the installation must be performed separately for each fuel cell stack, so the installation man-hours will increase.
It is an object of the invention to provide a fuel cell that is able to solve the aforementioned problems. More specifically, a major object of the invention is to prevent occurrence of torsion of a fuel cell stack disposed in a fuel cell housing case.
In order to achieve the aforementioned object, a fuel cell in accordance with an aspect of the invention includes: a fuel cell stack having a plurality of stacked unit cells and having a first electrode and a second electrode in two end portions of the fuel cell stack; a first end portion retaining member and a second end portion retaining member disposed in the two end portions of the fuel cell stack; and a fuel cell housing case that houses the fuel cell stack sandwiched by the first end portion retaining member and the second end portion retaining member and that retains the fuel cell stack by using a first retaining portion that retains a first end portion of a lower surface of the first end portion retaining member, a second retaining portion that retains a second end portion of the lower surface of the first end portion retaining member, and a third retaining portion that retains a central portion of a lower surface of the second end portion retaining member.
And a plurality of fuel cell stacks are provided in parallel, and the first end portion retaining member extends over the one end portions of the fuel cell stacks, and the second end portion retaining member extends over the other end portions of the fuel cell stacks.